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Summer high temperature is an important climate issue. Severe heat waves occurred over China during summer 2022. Using daily temperature, we examine the severity of the 2022 high‐temperature event, and explore the dominance of summer cumulative temperature from the frequency and intensity of high temperature, for both the interannual variation of the 63 years (1960–2022) and the year of 2022. Corresponding to different "high" temperature thresholds, the frequency (number of the days) of high temperature, the summer cumulative temperature, and the intensity of high temperature are obtained for each summer with the daily data. Statistical tests show that cumulative temperature can be linearly regressed to frequency and intensity, which can help find the dominance from the two factors. For interannual variation, the comparison of the normalized regression coefficients suggests that, in the variation of cumulative temperature, the relative importance can vary from "dominated by intensity", which corresponds to low temperature threshold (28°C), to "dominated by frequency", which corresponds to high threshold (36°C). For the year 2022, we compare the two terms in the regression, which uses the coefficients from multi‐year regression along with the normalized frequency and intensity of this year, to determine the relative importance. Results show that overall it also varies from "dominated by intensity" to "dominated by frequency", with the increase in threshold. Note that, for the two cases, these are the overall situation for the whole country; however, for each specific station, whether frequency or intensity dominates needs to be determined with the measures. A moderate threshold of 32°C, which considers both frequency and intensity, is suggested for practical applications. [ABSTRACT FROM AUTHOR]

Spherical mesoporous NiO powders were synthesized by a hydrothermal-thermal decomposition method, and their morphology and structure were investigated by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and N2 adsorption/desorption analysis. The electrocatalytic performance of NiO powders were systematically studied by cyclic vohammetry (CV), chronoamperometry (CA) and electrochemical impedance spectroscopy (EIS). It is found that the prepared mesoporous NiO powders are in spherical morphology with a specific surface area of 35 m2·g-1 and an average pore size of 15.88 nm. They show good electrocatalytic activity for ethanol oxidation; the oxidation current increases with increasing ethanol concentration and scan rate. The current decay at 0.60 V for 1000 s is as low as 0.075%, indicating good stability. CV, CA and EIS measurements show that ethanol oxidation reaction on the spherical mesoporous NiO is a diffusion-controlled process.

Climate science involves various functional relations and needs to investigate the dominance or relative importance of the variables in their relation. In our previous studies, we examined several problems in which causal relations are established, showing how the dependent quantity is affected by two or more independent variables. With linear fitting, the relative contributions of the variables to the variation of the quantity are compared. In this study, we examine constraint relation, which is a simultaneous multivariate relation, with all variables in the relation being equal in position. The relation can generally be nonlinear. To be convenient for examining the dominance, plane equation fitting can be used to linearize the relation. The equation of state for ideal dry air is investigated as a simple case of the relation. For this special case, a linearized relation can be obtained from both the fitting and the derivation. The scale analysis tool used in dynamic meteorology is applied here for the dominance analysis. Through comparing the scales of the terms, we can simplify the equation. The simplified relations correspond, respectively, to Charle's law, Boyle's law, and Gay-Lussac's law. The geographical preferences of the different dominance patterns are exhibited. In addition, when considering the change of the variable that is smallest in scale, we can identify which factor is the dominator. The ideal gas law is intentionally chosen as the example, since the relation is simple in form, and the results of dominance can be deduced analytically. A comparison demonstrates that the methods used here for the dominance analysis are reliable. [ABSTRACT FROM AUTHOR]

Northeast China (NEC) is an agricultural base of the country. It suffered a severe drought in 2014. During the drought, the western Pacific subtropical high is stronger than normal and stretches to the west. The warm and moist air in the southwest edge of the high transports northwestwards and thus cannot affect NEC. Over high latitudes, in the regions west and east to NEC, there are large anomalies in geopotential height, which favour meridional exchange and may lead to stronger‐than‐normal cold air intrusions. Because of the lack of warm and moist air supply from the south while the invasion of the cold and dry air from the north, the atmosphere over NEC is finally drier and colder than normal in saturation levels. Based on the physical relation between seasonal precipitation and relative humidity, along with the defined Cq and CT, indicators for measuring the changes in moisture and temperature, the effects of water vapour and air temperature on the drought can be linearly separated, and thus compared. Results reveal that, at middle and high levels, the dryness of the air, which plays a positive role in the drought, can offset the negative effect of the coldness, and the atmosphere over NEC then maintains a lower‐than‐normal relative humidity. In the near‐surface level, the air is drier and warmer than normal, which facilitates the drought. [ABSTRACT FROM AUTHOR]

Water vapor (WV) is a vital basis of water and energy cycles and varies with space and time. When researching the variations of moisture in the atmosphere, it is intuitive to think about the total WV of the atmosphere column, precipitable water (PW). It is an element that needs high-altitude observations. A surface quantity, surface WV pressure (SVP), has a close relationship to PW because of the internal physical linkage between them. The stability of their linkage at climatic scales is verified using monthly mean data from 1979 to 2021, while studies before mainly focused on daily and annual cycles in local areas. The consistency of their variations is checked with three reanalysis datasets from three angles, the interannual variations, the long-term trends, and the empirical orthogonal function (EOF) modes. Results show that the interannual correlation of SVP and PW can reach a level that is quite high and are significant in most areas, and the weak correlation mainly exists over low-latitude oceans. The long-term trends, as well as the first EOF modes of these two quantities, also show that their variations are consistent, with spatial correlation coefficients between the long-term trends of two variables that are generally over 0.6, but specific differences appearing in some regions including the Tropical Indian Ocean and Middle Africa. With the correspondence of PW and SVP, the variations of total column WV can be indicated by surface elements. The correspondence is also meaningful for the analysis of the co-variation in total column vapor and temperature. For example, we could research the relations between SVP and air temperature, and they can reflect the co-variance of total column vapor and near-surface air temperature, which can avoid analyzing the relation between column-integrated moisture content and surface air temperature directly. [ABSTRACT FROM AUTHOR]

It has generally been regarded that, in the warming climate, atmospheric water vapor may increase due to the enhancement in surface evaporation, which is expected from the Clausius–Clapeyron (C–C) equation, along with the assumption that relative humidity experiences small changes. If the variation in relative humidity is small, the response of water vapor to temperature will be closely in line with the C–C equation. However, whether relative humidity experiences large or small changes needs be assessed, and the change of relative humidity should be compared with the change in surface–air temperature. In this study, we link surface vapor pressure, which characterizes atmospheric water vapor, to surface-air temperature, and treat both the temperature and relative humidity as influencing factors. A method based on linear regression is applied to compare the interannual variabilities of relative humidity and temperature in the interannual variation in surface vapor pressure. Whether the year-to-year perturbation of relative humidity is important, compared with the perturbation in surface-air temperature, is explored Results show that, at high latitudes of both hemispheres, the variation in vapor pressure is dominated by air temperature, and relative humidity has small positive contributions. Thus, the variation in relative humidity over these regions is comparably small, and the response of water vapor to temperature can well follow the C–C equation. Differently, at mid-low latitudes, especially on land, air temperature plays a negative role in the variation in vapor pressure. Relative humidity offsets the negative contribution and dominates the variation in vapor pressure, suggesting that the variation in the relative humidity over these regions is comparably large. Hence, the response of water vapor to temperature deviate from the C–C equation. Analysis indicates that the different results of the dominance from the two influencing factors are affected by the dual effects of precipitation or wet-air transport over land. Both precipitation and the transport of cold wet air could break the C–C relation between water vapor pressure and temperature. [ABSTRACT FROM AUTHOR]

Harbin, located in northeast China (NEC), has obvious monsoon climate characteristics due to the influence of its geographical environment. Under the control of the polar continental air mass, winter in Harbin is exceedingly cold and long, with the frequent invasion of the cold and dry air from the north. Because of its intensely cold climate in winter, Harbin has created a local form of tourism with its own characteristics: the snow and ice landscape attracts a large number of tourists. Therefore, the anomalies of air temperature and precipitation in winter have an important impact on the livelihood of the local people and economy. In the winter of 2018/2019, the ice and snow tourism in Harbin was harshly affected by the extreme weather, and the direct cause is the anomalies of atmospheric circulation. There is a center of strong positive geopotential height anomalies over east China, which favors the movement of warm air northwards to the NEC, resulting in warmer-than-normal air temperature. Anomalous precipitation is largely controlled by the anomalies of local water vapor and air temperature. The aim of this study was to determine whether the warmer-than-normal temperature, which made the atmosphere more resistant to saturation, was the primary cause of the reduced snowfall. The relative importance of water vapor and air temperature anomalies to the anomalous precipitation was compared. The results suggest that the warmer-than-normal temperature affected all levels, but its impact on the near-surface level was greater. At the middle and upper levels (above 850 hPa), in addition to the warmer-than-normal temperature, the amount of water vapor was less than normal. These conditions both reduced the amount of snow; however, by comparison, the dryness of the air contributed more significantly. [ABSTRACT FROM AUTHOR]

It is certain that globally the troposphere has warmed since the industrial revolution because of the greenhouse gas emissions. The water vapour content of air increases as the climate warms. However, there is nonsignificant long‐term trend in global‐scale precipitation. This study aims to investigate the sources of the uncertainty of the long‐term precipitation trend under global warming through the water cycle. The data of the historical simulations (1850–2005) from 30 CMIP5 models are used in the estimate. The p‐value is utilized to indicate the significance of the long‐term trend of the water‐vapour‐related variable in the water cycle as well as the air temperature near surface and at the condensation level. For each variable, the p‐value is calculated for each of the grid points. The overall spatial distribution patterns of the p‐values are compared between two variables that linked directly, and a point‐to‐point comparison is also performed to the two fields. Results show that over the globe, the near‐surface specific humidity increases significantly at most of the grid points while the increase of the specific humidity at the condensation level is significant at some, and, however, the long‐term trend of the relative humidity at the condensation level is majorly nonsignificant. This suggests that as assessed from the global grid points, the uncertainty of the long‐term trend of the water‐vapour‐related variable enlarges substantially in the process of condensation, and modestly in the process of the transport of water vapour. Therefore, the uncertainty of the long‐term precipitation trend under global warming is mainly attributed to the condensation and slightly due to the transport of water vapour. The results obtained from the 30 models are consistent with each other, which supports the reliability of the conclusion. [ABSTRACT FROM AUTHOR]

In shock models, induction of endotoxin tolerance (ET) is known to have a protective effect. The present study was designed to explore if ET is effective in protecting lungs from reperfusion injury. Twelve foxhounds were used as experimental animals. After a left thoracotomy, the left hilum was clamped for 3 h, followed by 8 h of reperfusion. In the treatment group (ET, n = 6), dogs were pretreated with incremental daily endotoxin doses of up to 60 [micro]g/kg on day 6. The ischemia and reperfusion experiment was carried out on day 9. Control group animals (n = 6) were not subjected to endotoxin. Afar 8 h of observation, functional parameters of the reperfused lung of the ET and the control group were statistically different (P < 0.05) with respect to P[O.sub.2] [ET vs. control: 172.7 [+ or -] 12.9 vs. 66.1 [+ or -] 7.2 (SE) mmHg], compliance (16.0 [+ or -] 1.2 vs. 8.3 [+ or -] 1.0 ml/0.1 kPa), and the wet-to-dry ratio (9.4 [+ or -] 0.8 vs. 16.7 [+ or -] 1.2). After 3 h of warm ischemia and 8 h of reperfusion, pulmonary function and lung water content improved in the endotoxin-tolerant group. ischemia-reperfusion; acute respiratory distress syndrome; surfactant; lipopolysaccharide

In the context of global warming, the impact of summer high temperature events is increasing. The accumulated summer high temperature is often used to reflect the overall hotness of summer. The internal variation of the accumulated temperature can be affected by both the frequency and intensity. In this study, by using the daily data during summers of 1960–2018, we examine the relative importance of the two factors with a multiple linear regression method. It is demonstrated that that the dominant result of summer accumulated temperature is sensitive to the change of threshold. As the threshold increases, the importance of frequency gradually increases, while the importance of the intensity decreases. In addition, it is found that when the threshold changes, the sensitivity of the dominant results is different over regions. This can provide a basis for the selection of regional thresholds and further improve the representation of accumulated temperature for high summer temperatures. [ABSTRACT FROM AUTHOR]

The thermal forcing of the Tibet Plateau (TP) causes circulation anomalies that may affect the East Asian monsoon. Hence, summer precipitation in China has a close relation to the previous heat source over TP. The saturation of the atmosphere is the precondition of precipitation, so variations of vapour and temperature adjust the generation of precipitation synergistically. The heating of TP exerts impacts on summer precipitation in China, essentially, through modulating vapour and temperature. The goal of this study is to identify whether the variations of temperature or vapour dominate in the end. Besides, according to the heating characteristics over TP, a more accurate area of spring (March–May) heat source is chosen to indicate the midsummer (July) precipitation in China. The configuration of contributions of temperature and vapour can be divided into two cases. One is that vapour and temperature both increase or decrease, so they play inverse roles. It is easy to find the dominant element in this circumstance. The other is that vapour and temperature have concurrent effects. In this case, their significances need to be further compared. The method based on the linkage of the precipitation and relative humidity is used to quantitatively compare the effects of temperature and vapour. The results are robust and can complement the qualitative analysis with circulations and temperature. In years that there is intense heating on west TP, the Yangtze River basin (YZRB) is controlled by more vapour transport from oceans. The downstream of the Yellow River basin (YLRB) is affected by the dry and cold northerly winds. Dominance analysis shows that vapour general plays a more important role in two major river basins. Maybe not exactly coincide with someone's envision, not all the places are dominated by the vapour. Around northeast China, temperature contributes little more than vapour. [ABSTRACT FROM AUTHOR]

The spatial inhomogeneity of air pressure drives the atmospheric circulation. The interannual variation of the pressure can be affected by both air temperature and density. The goal of this study is to identify, for the near‐surface air, whether the variation of the density or temperature is more important in the interannual variation of the pressure. The physical relation of the pressure (P) with density (D) and temperature (T), denoted as P = D ⋅ T for simplicity, is nonlinear. To be convenient for estimating the relative importance, a normalized linear regression is used to fit the relation, which is finally written as P = AD + BT. Tests show that the linear fitting is robust; it is perfect everywhere in the globe. Because of the normalizations, the D and T are in magnitude of 1, but can be positive or negative. Derivations and calculations indicate that the coefficients A and B are both positive. What they reflect are the partial correlations of the pressure with the D and T, which are both equal to 1 across the entire field. For the normalized fitting, the A and B can be used to estimate the contributions of the D and T to the variation of the pressure. The linear fitting method can provide quantitative results for the dominance. The original nonlinear relation, due to the special form for the issue, can be used to qualitatively deduce the dominance. Comparisons suggest that the results obtained from the linear fitting are consistent with those qualitatively reached from the nonlinear physical relation. The consistency is true, no matter what the relation is between the two influencing factors. Corresponding to the negative relation between the density and temperature, there are two patterns. One is that the pressure increases with density but decreases with temperature. In this case, density dominates the variation of pressure. The second is that the pressure increases with temperature but decreases with density, and thus temperature dominates the variation of pressure. The third pattern is for the positive relation between density and temperature. In this case, density and temperature both have positive contributions to the variation of pressure, and which of them is more important can further be assessed with the linear fitting method. [ABSTRACT FROM AUTHOR]

Fluorescence emission and excitation spectra of para-phenylene vinylenes n PV with n = 1 -4 styryl units are investigated experimentally and theoretically as a function of the temperature and the polarizability of the solvent. At low temperatures, the vibronic structures of the So↔S[sub 1] emission and excitation bands are mirror symmetrical with negligible 0-0 energy gaps. The frequencies of the prominent vibrational modes are assigned to the second longitudinal acoustic phonon modes of the entire molecules and to localized carbon—carbon stretching vibrations. The complete vibronic structures of the spectra are calculated at the ab initio Hartree-Fock (HF/6-311G[sup *]) and restricted configuration interaction singles (RCIS/6-311G[sup *]) levels of theory assuming planar C[sub 2h] molecular symmetry. The theoretically predicted spectra are in good agreement with the experiments. At room temperature, a 0-0 energy gap between the first band maxima opens, and the mirror symmetry between absorption and emission is lost. The vibronic band shapes and 0-0 band gaps are successfully simulated with a combination of Gaussian and exponential broadening of the low temperature spectra. The exponential term reflects the differences in thermal population of the phenyl-vinyl torsional modes in the SO and S[sub 1] electronic states. Spectral shifts upon changes in temperature and solvents are quantitatively explained by changes in the refractive index of the environment. From extrapolation of the experimental data the vertical and adiabatic transition energies of the oligomers in vacuo are obtained and compared to RCIS and semi-empirical quantum chemical calculations, respectively. [ABSTRACT FROM AUTHOR]

In this study, cases of the East Asia-Pacific (EAP) teleconnection pattern not responsible for persistent precipitation processes in the Yangtze River valley (YRV) have been investigated. The results suggest that such a type of EAP pattern has some linkage with persistent precipitation processes in south China (SC) with the following properties: 1) in response to the negative SSTAs and anticyclone near the Philippines, the meridional energy propagates from the low latitudes over the north of the Philippines; 2) the western Pacific subtropical high (WPSH) then intensifies and extends westward; 3) a meridional triple structure of the EAP teleconnection pattern is established; 4) at the same time, the cyclonic circulation over northeastern China introduces cold and dry air to the lower latitudes, merging with the water vapor into SC and leading to heavy precipitation from the fringe of the WPSH, the South China Sea, and the Bay of Bengal and the combination of systems persists for at least 3 days, leading to the persistent precipitation processes in SC; and 5) compared with theEAP teleconnection responsible for the precipitation in YRV, the positions of the three centers in the mid- and low latitudes are more southerly located than theYRVEAP centers. Further study indicates that the ocean surface heat conditions in the areas near the Philippines seem to be important in affecting the EAP teleconnection pattern for persistent precipitation processes in SC. Finally, all of the cases with persistent precipitation in SC during 1961-2010 linked with the EAP pattern have been investigated; the results are consistent with the above conclusions. [ABSTRACT FROM AUTHOR]

The summer rainfall in China has a large interannual variability, which results from the concurrent variations of precipitation frequency and intensity. Using the observed daily precipitation in the 194 stations during recent 62 years, we examine the relative importance of the frequency and intensity in the variability of the rainfall. A simple method, based on linear regression, is used to estimate the relative importance. The products of the change rates of rainfall with respect to frequency and intensity, determined from the regression, and the corresponding standard deviations of the two variables, which reflect their variation scales, are defined to measure the importance of frequency and intensity. To determine the frequency, rainfall amount, and intensity from daily precipitation, we need a threshold to define the 'rainy day'. In this study, we use a series of thresholds, ranging from 1 to 30 mm/day. So, while presenting the result of relative importance for each threshold, we also examine how the relative importance varies with the threshold. Results show that for the threshold of 1 mm/day, with which the rainfall may include even the light rains, the variabilities of summer rainfall in most stations are dominated by intensity. With the increase in threshold, the importance of frequency increases, while the importance of intensity decreases. When the threshold reaches 30 mm/day, with which the rainfall includes only moderate-to-heavy rains, the variabilities of the rainfall in all stations are dominated by frequency. Analysis suggests that such a change, in the dominance with the threshold, is reasonable. This reasonability, in turn, supports the reliability and robustness of the method. [ABSTRACT FROM AUTHOR]

PURPOSE: To evaluate bone regeneration in defects at titanium implants with nHA/BG coating in conjunction with Bio--Oss. METHODS: Four mandibular premolars were extracted in 6 Beagle dogs. After 3 months, buccal dehiscence--type defects (2.25 mmx3 mmx4 mm) were surgically created following implant site. The three treatment modalities were randomly allocated: nHA/BG implant/Bio-Oss, nHA/BG implant/blood clot, and mHA implant/Bio-Oss. After 8 and 16 weeks, the dogs were sacrificed respectively. A histomorphometric analysis was performed. The data was analyzed with SPSS 13.0 software package for Student's t test and ANOVA. RESULTS: At 8- and 16-week, nHA/BG implant group revealed comparable mean BIC (30% to 18% versus 61% to 53%). However, mHA implant/Bio-Oss group revealed significantly lower mean BIC (21% versus 46%) values than nHA/BG implant/Bio-Oss group. A significant difference was observed for the mean BIC and RA values at 8-week between nHA/BG implant/Bio-Oss group and mHA implant/Bio-Oss group. CONCLUSIONS: It is concluded that the application of Bio-Oss graft did not seem to interfere with the nHA/BG coating activity, but ensured a stabilization of the newly formed bone for defects. [ABSTRACT FROM AUTHOR]

PURPOSE: To investigate the effect of induced- mineralization on the expression of SOST gene in human periodontal ligament cells, and explore the effect of SOST on periodontal tissues. METHODS: Human periodontal ligament cells were cultured by tissue explant in vitro, the cells were continuously induced by mineralization solution for 7,14 and 21 days. The mineralized ability, SOST and related osteogenie genes(ALP, OCN)expression were detected. The data was analyzed with SPSS 17.0 software package. RESULTS: Under the condition of mineralization solution in culture medium, human periodontal ligament cells had stronger ALP activity and Alizarin red staining, SOST and related osteogenic genes (ALP,OCN) expression were significantly upregulated in a time-dependent manner(P<0.05). CONCLUSIONS: After continuous induced- mineralization culture, human periodontal ligament cells can express SOST mRNA and related osteogenic genes in a time-dependent manner, which suggests that SOST may play a role in the regeneration of periodontal tissues. [ABSTRACT FROM AUTHOR]

Academic misconduct in medical research is mainly shown in the following nine aspects, including the irrational allocation of research topics and resources, significant bias of data collection, protection and sharing, ethical problems with imbalance of the benefits and risks for the subjects in scientific research, false signature in academic reports and academic publication, the problem of role and management in academic exchanges, the conflicts of interest, carelessness and injustice in the research management and peer review process, and the deficiency of education, training and guidance for the moral integrity of scientific research. The authors suggested the following precaution measures to improve the construction of the integrity of medical research, among them were strengthening of the organization and leadership by the medical institutions, improving the research evaluation mechanisms and the management system for the integrity of scientific research, reinforcing the education involving integrity of scientific research, and severely punishing academic misconduct. Supported by Science Innovation Foundation of Shanghai Municipal Education Commission(09YS108). [ABSTRACT FROM AUTHOR]

The thought of language is one of the most important aspects of Heidegger's ontological thought in his later period. He continued his early critique of traditional language thought which regards language simply as a tool of expression; but at the same time, compared with his earlier thought, he didn't treat Dasein as the centre of his research any longer, but paid more attention to being. For him, language names beings, by which beings become what they are. The nature of language is poetry. On the relationship between poetry and language, the two stipulate each other and become essence respectively. Heidegger's poetic view of language makes language return to its own foundation, by which human obtain their homeland of being. Therefore, a good deal of significant enlightment can be gained for returning to poetic existence. [ABSTRACT FROM AUTHOR]

Abstract: A Zn2SiO4 thin film was grown on silicon nanoporous pillar array (Si-NPA) via a chemical vapor deposition method, and the capacitive humidity-sensing properties of Zn2SiO4/Si-NPA were investigated at room temperature. With the relative humidity (RH) changing from 11% to 95%, the capacitance of the sensor increased from 1.67 to 135.97nF at the testing frequency of 20Hz, and an overall increment of 8042% was obtained. The response and recovery time was measured to be 48 and 32s, respectively. The sensor showed a maximum humidity hysteresis of 1.99% at 75% RH. These results indicated that Zn2SiO4/Si-NPA might be a promising material for fabricating high-performance capacitive humidity sensors. [Copyright &y& Elsevier]